ISpRecoContext::DeserializeResult (SAPI 5.4)

Article
08/26/2009

Microsoft Speech API 5.4

ISpRecoContext::DeserializeResult

ISpRecoContext::DeserializeResult creates a new result object from a serialized result.

  
    HRESULT DeserializeResult(
   const SPSERIALIZEDRESULT  *pSerializedResult,
ISpRecoResult            **ppResult
);

Parameters

pSerializedResult
[in] Pointer to a serialized result. See also SPSERIALIZEDRESULT
ppResult
[out] The unserialized result object. The application must call IUnknown::Release when finished using the ISpRecoResult reference.

Return values

Value

S_OK

E_INVALIDARG

E_POINTER

E_OUTOFMEMORY

FAILED(hr)

Remarks

After deserializing the ISpRecoResult object, the application can retrieve alternates for the RecoResult, retrieve the retained audio, or examine the recognition.

The same SR engine that was originally used to generate the ISpRecoResult object (or recognition) must be the same SR engine that is associated with the ISpRecoContext that called ::DeserializeResult (see SPPHRASE.SREngineID). The SR engine requirement ensures that the SR engine is capable of recognizing the original phrase, and that it understands any SR engine private result data (see SPPHRASE.ulSREnginePrivateDataSize).

Example

The following code snippet illustrates the use ISpRecoContext::Deserialize a previously serialized result object.

  
// Declare local identifiers:
HRESULT                    hr = S_OK;
CComPtr<ISpRecoResult>     cpRecoResult;
CComPtr<ISpRecoResult>     cpRecoResultNew;
CComPtr<IStream>           cpStreamWithResult;
CComPtr<ISpRecoContext>    cpRecoContext;
SPSERIALIZEDRESULT*        pSerializedResult = NULL;
ULONG                      cbWritten = 0;
ULONG                      ulSerializedSize = 0;
LARGE_INTEGER              liseek;
LARGE_INTEGER              li;

// ... Obtain a recognition result object from the recognizer ...
hr = CreateStreamOnHGlobal(NULL, true, &cpStreamWithResult;);

if (SUCCEEDED(hr))
{
   // Serialize result to memory.
   hr = cpRecoResult->Serialize(&pSerializedResult;);
}

if (SUCCEEDED(hr))
{
   // Serialize to a stream pointer.
   hr = cpStreamWithResult->Write(pSerializedResult, pSerializedResult->ulSerializedSize, &cbWritten;);
}

if (SUCCEEDED(hr))
{
   // Free the serialized result.
   if (pSerializedResult) ::CoTaskMemFree(pSerializedResult);

   // Commit the stream changes.
   hr = cpStreamWithResult->Commit(STGC_DEFAULT);
}

if (SUCCEEDED(hr))
{
   // ... Persist stream to disk, network share, etc ...
   // ... Shutdown application ...
   // ... Restart application and get the persisted stream ...

   // Reset the stream seek pointer to the start before deserialization:
   li.QuadPart = 0;
   hr = cpStreamWithResult->Seek(li, STREAM_SEEK_SET, NULL);
}

if (SUCCEEDED(hr))
{
   // Find the size of the stream.
   hr = cpStreamWithResult->Read(&ulSerializedSize;, sizeof(ULONG), NULL);
}

if (SUCCEEDED(hr))
{
   // Reset the seek pointer:
   liseek.QuadPart = 0 - sizeof(ULONG);
   hr = cpStreamWithResult->Seek(liseek, STREAM_SEEK_CUR, NULL);
}

if (SUCCEEDED(hr))
{
   // Allocate the memory for the result.
   pSerializedResult = (SPSERIALIZEDRESULT*)::CoTaskMemAlloc(ulSerializedSize);

   // Check pSerializedResult in case out "out-of-memory".

   // Copy the stream into a serialized result object.
   hr = cpStreamWithResult->Read(pSerializedResult, ulSerializedSize, NULL);
}

if (SUCCEEDED(hr))
{
   // Deserialize result from memory.
   hr = cpRecoContext->DeserializeResult(pSerializedResult, &cpRecoResultNew;);
}

if (SUCCEEDED(hr))
{
   // Free the pSerializedResult memory.
   if (pSerializedResult) CoTaskMemFree(pSerializedResult);
}

// As long as the same engine was used to generate original
// result object, as is now being used, applications can
// now get alternates for the cpRecoResultNew's phrase.

Partager via